diff options
Diffstat (limited to 'win32/crc_i386.c')
| -rw-r--r-- | win32/crc_i386.c | 152 |
1 files changed, 117 insertions, 35 deletions
diff --git a/win32/crc_i386.c b/win32/crc_i386.c index e8a2faf..971ee66 100644 --- a/win32/crc_i386.c +++ b/win32/crc_i386.c @@ -1,13 +1,14 @@ /* - Copyright (c) 1990-2005 Info-ZIP. All rights reserved. + Copyright (c) 1990-2007 Info-ZIP. All rights reserved. - See the accompanying file LICENSE, version 2004-May-22 or later + See the accompanying file LICENSE, version 2000-Apr-09 or later (the contents of which are also included in zip.h) for terms of use. - If, for some reason, both of these files are missing, the Info-ZIP license + If, for some reason, all these files are missing, the Info-ZIP license also may be found at: ftp://ftp.info-zip.org/pub/infozip/license.html */ /* crc_i386.c -- Microsoft 32-bit C/C++ adaptation of crc_i386.asm * Created by Rodney Brown from crc_i386.asm, modified by Chr. Spieler. + * Last revised: 07-Jan-2007 * * Original coded (in crc_i386.asm) and put into the public domain * by Paul Kienitz and Christian Spieler. @@ -56,6 +57,16 @@ * Also enabled the 686 build by default, because there are hardly any * pre-686 CPUs in serious use nowadays. (See the 12-Oct-97 note above.) * + * Revised 03-Jan-2006, Chr. Spieler + * Enlarged unrolling loops to "do 16 bytes per turn"; optimized access to + * data buffer in loop body (adjust pointer only once in loop body and use + * offsets to access each item); added additional support for the "unfolded + * tables" optimization variant (enabled by IZ_CRCOPTIM_UNFOLDTBL). + * + * Revised 07-Jan-2007, Chr. Spieler + * Recognize additional conditional flag CRC_TABLE_ONLY that prevents + * compilation of the crc32() function. + * * FLAT memory model assumed. * * Loop unrolling can be disabled by defining the macro NO_UNROLLED_LOOPS. @@ -64,8 +75,9 @@ */ #include "../zip.h" +#include "../crc32.h" -#if defined(ASM_CRC) && !defined(USE_ZLIB) +#if defined(ASM_CRC) && !defined(USE_ZLIB) && !defined(CRC_TABLE_ONLY) #if !defined(PRE_686) && !defined(__686) # define __686 @@ -119,14 +131,64 @@ __asm { inc esi }; \ Do_CRC; } +#define Do_CRC_byteof(ofs) { \ + __asm { xor al, byte ptr [esi+(ofs)] }; \ + Do_CRC; } + #ifndef NO_32_BIT_LOADS +#ifdef IZ_CRCOPTIM_UNFOLDTBL +# define SavLen len /* the edx register is needed elsewhere */ +# define UpdCRC_dword { \ + __asm { movzx ebx,al }; \ + __asm { mov edx,[edi+ebx*4+3072] }; \ + __asm { movzx ebx,ah }; \ + __asm { shr eax,16 }; \ + __asm { xor edx,[edi+ebx*4+2048] }; \ + __asm { movzx ebx,al }; \ + __asm { shr eax,8 }; \ + __asm { xor edx,[edi+ebx*4+1024] }; \ + __asm { mov eax,[edi+eax*4] }; \ + __asm { xor eax,edx }; } +# define UpdCRC_dword_sh(dwPtrIncr) { \ + __asm { movzx ebx,al }; \ + __asm { mov edx,[edi+ebx*4+3072] }; \ + __asm { movzx ebx,ah }; \ + __asm { xor edx,[edi+ebx*4+2048] }; \ + __asm { shr eax,16 }; \ + __asm { movzx ebx,al }; \ + __asm { add esi, 4*dwPtrIncr }; \ + __asm { shr eax,8 }; \ + __asm { xor edx,[edi+ebx*4+1024] }; \ + __asm { mov eax,[edi+eax*4] }; \ + __asm { xor eax,edx }; } +#else /* !IZ_CRCOPTIM_UNFOLDTBL */ +# define SavLen edx /* the edx register is free for use here */ +# define UpdCRC_dword { \ + Do_CRC; \ + Do_CRC; \ + Do_CRC; \ + Do_CRC; } +# define UpdCRC_dword_sh(dwPtrIncr) { \ + Do_CRC; \ + Do_CRC; \ + __asm { add esi, 4*(dwPtrIncr) }; \ + Do_CRC; \ + Do_CRC; } +#endif /* ?IZ_CRCOPTIM_UNFOLDTBL */ + #define Do_CRC_dword { \ __asm { xor eax, dword ptr [esi] }; \ - __asm { add esi, 4 }; \ - Do_CRC; \ - Do_CRC; \ - Do_CRC; \ - Do_CRC; } + UpdCRC_dword_sh(1); } + +#define Do_CRC_4dword { \ + __asm { xor eax, dword ptr [esi] }; \ + UpdCRC_dword; \ + __asm { xor eax, dword ptr [esi+4] }; \ + UpdCRC_dword; \ + __asm { xor eax, dword ptr [esi+8] }; \ + UpdCRC_dword; \ + __asm { xor eax, dword ptr [esi+12] }; \ + UpdCRC_dword_sh(4); } #endif /* !NO_32_BIT_LOADS */ /* ========================================================================= */ @@ -170,46 +232,66 @@ align_loop: jnz align_loop aligned_now: # endif /* !NO_32_BIT_LOADS */ - mov edx,ecx ;/* save len in edx */ - shr ecx,3 ;/* ecx = len / 8 */ - jz No_Eights + mov SavLen,ecx ;/* save current len for later */ + shr ecx,4 ;/* ecx = len / 16 */ + jz No_Sixteens ; align loop head at start of 486 internal cache line !! align 16 -Next_Eight: +Next_Sixteen: } # ifndef NO_32_BIT_LOADS - Do_CRC_dword ; - Do_CRC_dword ; + Do_CRC_4dword ; # else /* NO_32_BIT_LOADS */ - Do_CRC_byte ; - Do_CRC_byte ; - Do_CRC_byte ; - Do_CRC_byte ; - Do_CRC_byte ; - Do_CRC_byte ; - Do_CRC_byte ; - Do_CRC_byte ; + Do_CRC_byteof(0) ; + Do_CRC_byteof(1) ; + Do_CRC_byteof(2) ; + Do_CRC_byteof(3) ; + Do_CRC_byteof(4) ; + Do_CRC_byteof(5) ; + Do_CRC_byteof(6) ; + Do_CRC_byteof(7) ; + Do_CRC_byteof(8) ; + Do_CRC_byteof(9) ; + Do_CRC_byteof(10) ; + Do_CRC_byteof(11) ; + Do_CRC_byteof(12) ; + Do_CRC_byteof(13) ; + Do_CRC_byteof(14) ; + Do_CRC_byteof(15) ; + __asm { add esi,16 }; # endif /* ?NO_32_BIT_LOADS */ __asm { dec ecx - jnz Next_Eight -No_Eights: - mov ecx,edx - and ecx,000000007H ;/* ecx = len % 8 */ - + jnz Next_Sixteen +No_Sixteens: + mov ecx,SavLen + and ecx,00000000FH ;/* ecx = len % 16 */ +# ifndef NO_32_BIT_LOADS + shr ecx,2 + jz No_Fours +Next_Four: + } + Do_CRC_dword ; + __asm { + dec ecx + jnz Next_Four +No_Fours: + mov ecx,SavLen + and ecx,000000003H ;/* ecx = len % 4 */ +# endif /* !NO_32_BIT_LOADS */ #endif /* !NO_UNROLLED_LOOPS */ - jz bail ;/*> if (len) */ + jz bail ;/*> if (len) */ ; align loop head at start of 486 internal cache line !! align 16 -loupe: ;/*> do { */ +loupe: ;/*> do { */ } - Do_CRC_byte ;/* c = CRC32(c, *buf++); */ + Do_CRC_byte ;/* c = CRC32(c,*buf++,crctab);*/ __asm { - dec ecx ;/*> } while (--len); */ + dec ecx ;/*> } while (--len); */ jnz loupe -bail: ;/*> } */ - not eax ;/*> return ~c; */ +bail: ;/*> } */ + not eax ;/*> return ~c; */ fine: pop ecx pop edx @@ -225,4 +307,4 @@ fine: # pragma warning( default : 4035 ) #endif #endif -#endif /* ASM_CRC && !USE_ZLIB */ +#endif /* ASM_CRC && !USE_ZLIB && !CRC_TABLE_ONLY */ |